Generally speaking, when a piece of furniture (e.g., a drawer, cabinet, or door) or equipment undergoes an earthquake of a certain magnitude, some moving part or parts of the furniture or equipment tend to move (e.g., open or close) on their own with respect to a stationary part. To prevent accidents that could arise from such unintended operation, safety devices were developed. For example, U.S. Pat. No. 6,550,827 B1 discloses a closing device of a hinged door, wherein the hinged door (32) is provided in a storing device main body (31). The closing device includes a case (33), a locking member (38), and at least one spherical member (37) above the locking member (38). When an earthquake takes place, the spherical member (37) prevents the locking member (38) from moving upward and thereby controls the angle by which the hinged door (32) may be opened by the earthquake.
As furniture or equipment that requires such a safety device varies widely, it is important to develop different products so that consumers are supplied with more choices.